PATHOLOGY

Detailed explanation-1: -Cells enter G0 for varying amounts of time, and some cells enter the G0 phase and stay there forever. Some examples of cells that enter G0 and stay forever are nerve cells and heart cells. This is because once they reach maturity, nerve and heart cells do not divide again, so they stay in the G0 phase.

Detailed explanation-2: -Some cells in the adult animals do not appear to exhibit division (e.g., heart cells) and many other cells divide only occasionally. These cells that do not divide further exist G1 phase to enter an inactive stage called quiescent stage (G0) of the cell cycle.

Detailed explanation-3: -Most liver cells, for example, are in G0, but they can be stimulated to divide if the liver is damaged.

Detailed explanation-4: -The G0 phase describes a cellular state outside of the replicative cell cycle. Classically, cells were thought to enter G0 primarily due to environmental factors, like nutrient deprivation, that limited the resources necessary for proliferation. Thus it was thought of as a resting phase.

Detailed explanation-5: -For instance, tissue stem are cells (e.g. muscle stem cells, intestinal stem cells, neural stem cells, etc.) remain in Gap 0 phase and be in a quiescent state for an indefinite period until external stimuli activate them into re-entering the remaining phases of the cell cycle all through cell division.